[ 3 posts ]

 Print view Previous topic | Next topic

#### DS: co ordinate

Author Message
 Post subject: DS: co ordinate  Posted: Mon Mar 05, 2012 2:32 pm
 Students

Posts: 51
 if ab is not = 0 and point (-a,b) and (-b,a) are in same quadrant of the xy plane , is the point (-x,y) in this same quadrant??(1) xy>0(2) ax>0OA: ci selected answer B... thinking that if ax>0 => signs of a and x are same, therefore -a and -x shud point out to same side of origin for the x coordinate of the point. However now i think that confirming xy>0 is also needed because if x and y are not of same sign then even if x lies in same side of x axis (either left or right of origin) but if y is of different sign then point cannot be in the same quadrant as (-a,b)... please let me know if my way of thinking is correct .. or if there is any other way of looking at this problem..Tanya

 Post subject: Re: DS: co ordinate  Posted: Mon Mar 05, 2012 10:11 pm
 Students

Posts: 8
 you are right. Having (-a, b) and (-b, a) => both a and b should be of same sign. If both positive, II quad else IV quadA) xy >0 - Insufficient. Though even (-x, y) will either belong to II or IV quad, it could be opposite to where (-a,b) or (-b,a) B) ax >0 - Insufficient. Though we know the sign of x, we cannot confirm which quadrant (-x, y) will belong to due to dependency on yA + B - Sufficient

 Post subject: Re: DS: co ordinate  Posted: Wed Mar 07, 2012 8:15 pm
 ManhattanGMAT Staff

Posts: 8057
 please search the forum for existing threads before posting! (we may restrict the posting privileges of users who create too many new threads on problems for which threads already exist, since that just makes it harder for all users to find what they are looking for.)here is a very long and exhaustive post on this one:post10305.html#p10305this thread is now locked; if you have questions, please post them on the linked thread. _________________Being well-dressed gives a feeling of inward tranquillity [that] religion is powerless to bestow.C.F. Forbes

Display posts from previous:  Sort by

[ 3 posts ]

#### Who is online

 Users browsing this forum: No registered users and 1 guest

 You cannot post new topics in this forumYou cannot reply to topics in this forumYou cannot edit your posts in this forumYou cannot delete your posts in this forumYou cannot post attachments in this forum

Search for:
 Jump to:  Select a forum ------------------ Ask An Instructor    General GMAT Strategy Questions    GMAT Math       General Math Questions       GMAT Prep Math       Manhattan GMAT CAT Math       Manhattan GMAT Non-CAT Math       Official Guide Math    GMAT Verbal       General Verbal Questions       GMAT Prep Verbal       Manhattan GMAT CAT Verbal       Manhattan GMAT Non-CAT Verbal       Official Guide Verbal    GMAT Integrated Reasoning (IR)       GMAT Prep IR       Manhattan GMAT CAT IR       Manhattan GMAT Non-CAT IR    GMAT AWA Essays Manhattan GMAT    Ask Student Services    Study Groups    GMAT Test Day    Test Centers    Instructor Feedback    Course Feedback B-School    Ask an mbaMission Admissions Consultant    B-School Essays    Business Schools    Professional Networking